A relatively new entrant to the instant coffee market is flavored instant coffee. Typically, a flavored instant coffee contains a mixture of instant coffee particles, creamer, sweetener, and flavorings. A key challenge in flavored instant coffee products is to provide the right amount and balance of coffee and characteristic flavor, e.g., vanilla, chocolate, hazelnut. Increasing the coffee and characteristic flavor perception without increasing the level of the respective flavor ingredient or throwing the flavor equilibrium out of balance can be difficult. Other key product attributes, primarily creaminess and sweetness perception, and solubility also need to be maintained.
Current flavored instant coffee products on the market provide an essentially uniform appearance in terms of color and particle size. A variegated appearance in both color and particle size for flavored instant coffee powders can be desirable in enhancing the various flavor components, e.g., having brown clusters mixed in a white powder to enhance the coffee and vanilla flavor perception respectively or having brown clusters mixed in a reddish chocolate powder to enhance the coffee and chocolate raspberry flavor perception, respectively. However, achieving the right variegated appearance in a flavored instant coffee is not a trivial task. Simply mixing darker and lighter colored particles of different sizes will not provide a contrasting color appearance because the smaller flavor particles (i.e., the cocoa, coffee and other flavors) tend to uniformly coat the larger particles (typically sugar and creamer). In addition, when much larger particles are mixed together with a fine powder, the larger particles tend to segregate out of the mixture, forming a layer on top of the powder. Therefore, it would be desirable to have the smaller particles be agglomerated in such a way that they remain attached to the specific particles they are agglomerated to, yet easily disintegrate in solution. In addition, it would be desirable to be able to agglomerate the particles such that two distinct, separate colored streams are obtained that do not segregate when combined.
Various methods are known for agglomerating powders, each producing an agglomerate that is physically and visually unique. Agglomeration can improve solubility by increasing both wetting time and porosity. However, if agglomeration results in particles that are too dense or strong, it can have the opposite effect, i.e., reduce solubility. Further, if the agglomerated particles are too coarse, specific attributes such as creaminess and sweetness that are important to flavored instant coffee products can be perceived as being lower in the agglomerated products. Therefore, it would be desirable to have a particular particle size distribution that allows certain agglomerated particles that enhance the flavor attributes to be visible, yet maintains a somewhat powdery form without significant particle segregation.
A dense, strong agglomerate is desirable for a flavored instant coffee product. Particle strength is important in maintaining the desired particle size distribution and appearance. The bulk density of the agglomerated product should also allow a dosage equivalent to the unagglomerated (powder) form of the product containing the same ingredients. In addition, agglomerates having these characteristics still need to be rapidly soluble in water.